KR100222459B1 - Process for producing hydrochloromethanes - Google Patents

Abstract

The present invention relates to a method for producing hydrous chloromethanes such as chloroform in high selectivity and high yield by reducing polychloromethanes of carbon tetrachloride in the presence of a reducing catalyst.

In the present invention, it is important to make the reduction reaction in the liquid phase, thereby effectively suppressing by-products of impurities such as a polymer which inactivates the catalyst, thereby sufficiently exhibiting high selectivity and high activity of the reduction catalyst.

As the reduction catalyst, at least one kind selected from Group 8, Group 9 and Group 10 elements such as ruthenium, rhodium, palladium and platinum is suitably employed, and these elements are mainly composed of copper, silver, gold and the like. The catalyst which added at least 1 sort (s) of group 11 element of can also be employ | adopted suitably.

In the case of performing the liquid phase reduction reaction continuously, the use of the fixed bed method is preferable, and the dropping method is particularly preferable.

The method of the present invention is also highly valuable as a method of converting carbon tetrachloride, which is regulated from the standpoint of global environmental protection, into chloroform or the like useful as a raw material for various fluorine compounds.

Description

[Name of invention]

Method for preparing water-containing chloromethanes

Detailed description of the invention

[Industrial use]

The present invention relates to a method for converting polychloromethanes, particularly carbon tetrachloride, which is regulated from the standpoint of global environmental protection, into hydrous chloromethanes such as chloroform, which are useful as raw materials for various fluorine compounds. will be.

Background Technology

Conventionally, carbon tetrachloride has been mainly used as a raw material for various freons. However, since the production of carbon tetrachloride, which is a raw material, is regulated, the technique for decomposing these or converting them into useful ones is widely required worldwide.

On the other hand, hydrous chloromethanes such as chloroform obtained by substituting a chlorine atom in carbon tetrachloride with a hydrogen atom are useful as raw materials for various chemical products. Therefore, there is a rapid demand for the development of technology to efficiently convert hydrogen into polychloromethanes of carbon tetrachloride and convert them into hydrous chloromethanes.

Various methods are known as a method of introducing hydrogen into carbon tetrachloride. The method of electrolytic reduction in the presence of a protic solvent has disadvantages such as a slow reaction rate, so it is difficult to employ it industrially.

On the other hand, the method of hydrogen reduction using a reducing catalyst such as Japanese Patent Application Laid-open No. 3-133939 has a high reaction rate and can also use hydrogen chloride as a by-product, which is considered to be advantageous for industrial use. However, the method disclosed in Japanese Patent Laid-Open No. 3-133939 is a gas phase effort reduction method using a general catalyst such as iron or platinum, and it has been found that the catalyst activity decreases in a very short time. In addition, in the gas phase hydrogen reduction method of carbon tetrachloride, for example, dimers such as hexachloroethane and, in particular, high temperature, by-products of 5 to 7 carbon atoms are by-produced, the yield of the desired product is not necessarily high. .

The present inventors studied variously about the said gaseous-phase hydrogen reduction method. First, the organic components on the deactivated catalyst were analyzed and found to be mostly synthetic. In addition, the particle size of the catalyst was almost the same as that of the non-use when observed by a transmission electron microscope and analyzed by X-ray diffraction. Therefore, it was estimated that deposition of a polymer is a main inert cause.

[Initiation of invention]

The present inventors earnestly examined about the reaction method which suppresses rapid inactivation of a catalyst. As a result, it has been found that short-term deterioration of the catalyst is eliminated by adopting a method of reducing polychloromethanes to hydrogen in a liquid state in the presence of a reducing catalyst, and chloromethanes are obtained as a function with high yield. The present invention has been completed based on the above findings, and provides a method for producing hydrous chloromethane, wherein polychloromethane is reduced by hydrogen in the liquid phase in the presence of a reducing catalyst. Hereinafter, the present invention will be described in detail with examples.

Polychloromethanes are carbon tetrachloride, chloroform and methylene chloride. According to the method of the present invention, chloroform, methylene chloride and methyl chloride are obtained by reduction of carbon tetrachloride, methylene chloride and methyl chloride are obtained by reduction of chloroform, and methyl chloride is obtained by reduction. As polychloromethane, carbon tetrachloride which is regulated is preferable.

Carbon tetrachloride is a molecule in which four polar chlorine atoms are bonded to a carbon atom, and has very high adsorption energy in halogenated methane. Therefore, the residence time on the catalyst is long, and has the property of being prone to catalysis. Therefore, when a catalyst composed of elements having a high reducing activity selected from Groups 8, 9 and 10 is used, the formation of olefins and the formation of polymers are remarkable, and thus tends to be inactivated in a very short time. Especially in the gas phase reaction method, since the reaction temperature is basically high, olefins are produced. It is contemplated that polymerization is liable to occur and that the resulting polymer is generally high in boiling point and therefore difficult to remove from the catalyst surface. This is thought to be the cause of the rapid deactivation.

On the other hand, the reaction in the liquid phase tends to complicate the reaction system, but it is easy to control the adsorption of carbon tetrachloride by the use of a reaction solvent, and the degree of polymerization is not so great in the by-product polymer and it is easy to dissolve and remove from the catalyst surface. It is thought to have the advantage of being able to suppress the reduction of the active point. Therefore, as a result of studying the optimization of the reaction conditions and the catalyst, it was found that water-containing chloromethanes such as chloroform, methylene chloride, methyl chloride and the like were obtained with high selectiveness without the sudden deactivation of the catalyst. .

As the reduction catalyst, a catalyst having a main component of at least one element selected from Group 8 elements of iron, ruthenium and osmium, Group 9 elements of cobalt, rhodium and iridium, and Group 10 elements of nickel, palladium and platinum is preferable. The catalyst which has such a group 8, 9, and 10 element as a main component may be a catalyst which consists only of these elements, or the catalyst which added and used together metal elements other than group 8-10 elements with these elements may be used together.

Among the Group 8-10 elements as the main component, platinum group elements such as palladium, ruthenium, platinum, and rhodium are particularly preferable because of high activity and high durability. Moreover, group 11 elements, such as copper, silver, and gold, can be illustrated as an addition component. Both the main component element and the additive component element may be used in one kind, or two or more kinds may be used in combination. When using an additive component together, the addition amount thereof is 0.01-50 weight%, Preferably it is 0.1-50 weight%, Especially 1-50 weight% is preferable.

These catalyst metals can be used as they are or supported on a carrier. As the carrier, those commonly used such as activated carbon, alumina, zirconia, silica and the like can be used. In terms of the supported amount, about 0.01 to 20% by weight, and preferably about 0.5 to 5% by weight, are suitable from the viewpoint of supporting efficiency of the catalyst, reaction activity, dispersion of catalyst components, and the like.

The method of supporting the catalyst component can also be appropriately selected within a range generally employed. For example, the method of supporting by the impregnation method, the ion exchange method, etc. using the simple salt or complex salt of the said element is applicable. In the use of the catalyst, it is not necessary to necessarily reduce the catalyst, but it is preferable to carry out hydrogen reduction in advance to obtain stable characteristics. As a method of reducing the supported catalyst component, a method of reducing to a liquid phase by hydrogen, hydrazine, formaldehyde, sodium borohydride, or the like, a method of reducing to a gas phase by hydrogen, or the like may be applied.

As the liquid phase reaction process, any of a fixed phase and a suspended phase can be employed. The use of reaction solvent is effective for controlling the product ratio, stabilizing the reaction activity, and the like. For example, alcohols such as methanol and ethanol, amines such as triethylamine, carboxylic acids such as acetic acid and ketones such as aceron can be used as the reaction solvent.

In the case of continuously performing the liquid phase reduction reaction in the present invention, it is preferable to employ a liquid phase stationary phase system in which the raw material liquid is brought into contact with the stationary phase of the reduction catalyst. Particularly, in the dropwise phase system in which the raw material liquid is supplied in the downflow, the liquid phase diffusion distance of hydrogen is short and it is easy to suppress the decrease in the hydrogen concentration on the surface of the catalyst, which is advantageous in improving the reaction rate and the catalyst durability. In the liquid stationary bed system, it is preferable to use a catalyst having a catalyst metal supported on a carrier. As the carrier, one having a strength that is not differentiated by the circulation of the liquid is employed. The shape of the carrier is particularly suitable for pellets, which are hard to suffer from abrasion loss when the raw material liquid is circulated in an upflow. However, in the dropwise loading method, crushed coal or the like can be used, but is not necessarily limited. The size of the catalyst is not particularly limited, but is usually about 0.5 to 20 mm in diameter.

The temperature of the liquid phase reduction reaction is 0 To 200 , Preferably 50 To 150 It is suitable to do. The reaction molar ratio of hydrogen and polychloromethanes is not particularly limited. When the hydrogen is used a lot, the reaction rate increases, but the dechlorination hydrogenation proceeds more and the production rate increases. It is preferable to use about 0.1-10 mol of hydrogen with respect to 1 mol of polychloromethanes. Excess hydrogen can be circulated to increase the utilization efficiency of hydrogen.

In addition, the reaction pressure is more than normal pressure, the reaction rate increases as the pressure increases. Can kg / cm ² G ~ 10kg / cm ² Pressurization up to about G may be employed. At too high a pressure, even if the reaction rate increases, difficulties such as an increase in the device cost are recognized.

Best Mode for Carrying Out the Invention

Example 1

Inner capacity 2 In the autoclave of 1 Activated carbon supported metal catalyst with carbon tetrachloride (supporting amount: 2% by weight, yen this 10 g of Chemcat Co., Ltd. was added. Encapsulated Nitrogen 110 After the temperature was raised to, the hydrogen supply was started. Pressure is 5kg / cm ² G. As for the product, all of the gaseous components and liquid components were analyzed using gas chromatography. The reaction was continued by supplying 3 mol of hydrogen continuously with respect to 1 mol of carbon tetrachloride. After the start of the reaction, the carbon tetrachloride reaction rate was 91% at 1,000 hours, and formation of chloroform (selectivity: 70%), perchloroethylene (selectivity: 18%) and the like were confirmed.

Example 2

Inner capacity 2 In the autoclave of 1 Palladium-supported palladium catalyst with carbon tetrachloride (supporting amount: 2% by weight, yen this 50 g of Chemcat Co., Ltd. was added. After filling with nitrogen, 115 The temperature was raised to and the hydrogen supply was started. Pressure is 5kg / cm ² G. As for the product, all of the gaseous components and liquid components were analyzed using gas chromatography. The reaction was continued by supplying 4 mol of hydrogen continuously with respect to 1 mol of carbon tetrachloride. After the start of the reaction, the reaction rate of carbon tetrachloride in 1000 hours was 92%, and formation of chloroform (selectivity: 60%), methylene chloride (selectivity: 9%), perchloroethylene (selectivity: 17%) and the like were confirmed.

Example 3

Inner capacity 2 In the autoclave of 1 Zirconia-supported rhodium catalyst with carbon tetrachloride (supporting amount: 2% by weight, yen this Chemcat Co.) was added 50%. After filling with nitrogen, 110 The temperature was raised to and the hydrogen supply was started. Pressure is 5kg / cm ² G. As for the product, all of the gaseous components and liquid components were analyzed using gas chromatography. The reaction was continued by supplying 3 mol of hydrogen continuously with respect to 1 mol of carbon tetrachloride. The reaction rate of carbon tetrachloride at 1000 hours after the start of the reaction was 93%, chloroform (selectivity: 58%), methylene chloride (selectivity: 8%), methyl chloride (selectivity: 7%), perchloroethylene (selectivity: 16% ) Was confirmed.

Example 4

Inner capacity 2 In the autoclave of 1 Of carbon tetrachloride and activated carbon supported ruthenium catalyst (supporting amount: 5% by weight, yen this 50 g of Chemcat Co., Ltd. was added. 120 after filling with nitrogen The temperature was raised to and the hydrogen supply was started. Pressure is 5kg / cm ² G. As for the product, all of the gaseous components and liquid components were analyzed using gas chromatography. The reaction was continued by supplying 5 mol of hydrogen continuously with respect to 1 mol of carbon tetrachloride. The reaction rate of carbon tetrachloride at 1000 hours after the start of the reaction was 89%, chloroform (selectivity: 58%), methylene chloride (selectivity: 9%), methyl chloride (selectivity: 14%), perchloroethylene (selectivity: 18% ) Was confirmed.

Comparative Example 1

Activated carbon supported platinum catalyst (support amount: 0.5% by weight, yen this 100g of Chemcat Co., Ltd. was put in an Inconel reaction tube with an inner diameter of 0.5 inch, and 160 It was immersed in the heat medium set as. After treating with nitrogen in advance and hydrogen in advance, hydrogen was introduced at a rate of 2 mol to 1 mol of carbon tetrachloride, and the reaction was carried out in the gas phase. At 7 seconds of contact time, the reaction pressure was atmospheric pressure. The reaction rates of carbon tetrachloride at 2 hours and 20 hours after the start of the reaction were about 90% and about 30%, respectively. After that, the reaction rate was inactivated as time passed. As the product, chloroform, methylene chloride, methyl chloride, methane, and other chlorinated alkanes and alkenes having 2 to 5 carbon atoms such as perchloroethylene were recognized.

Example 5

Platinum catalyst supported on coal briquettes with a diameter of 3mm (supporting amount: 2% by weight, yen this Chemcat Co., Ltd.) 4 Was charged into a 60 mm cylindrical reactor. After the catalyst layer was filled with carbon tetrachloride, oxygen was enclosed. 80 After the temperature was raised to, the hydrogen supply was started. The reaction was continued by supplying 3 mol of hydrogen per continuously and upflow with respect to 1 mol of carbon tetrachloride. The generated gas components such as chloroform were continuously taken out by the gas-liquid separator, and the liquid components such as unreacted carbon tetrachloride were returned to the reactor and circulated. Pressure is 5kg / cm ² G. As for the product, both gaseous and liquid components were analyzed using gas chromatography. After the start of the reaction, the reaction rate in one pass of carbon tetrachloride in 100 hours was 91%, and formation of chloroform (selectivity: 90%), perchloroethylene (selectivity: 5%) and the like were confirmed.

Example 6

Palladium catalyst supported on coal briquettes having a diameter of 5 mm as a catalyst (supporting amount: 2% by weight, yen this The same procedure as in Example 5 was conducted except that Chemcat Co., Ltd. was used, and the product was analyzed. After the start of the reaction, the reaction rate in one pass of carbon tetrachloride in 100 hours was 92%, and formation of chloroform (selectivity: 85%), perchloroethylene (selectivity: 10%), methane (5%) and the like were confirmed. .

Example 7

Platinum catalyst supported by coal briquettes with a diameter of 1mm (supporting amount: 2% by weight, yen this Chemcat company) 1 Was charged into an internal diameter 30 mm cylindrical reactor. 80 after filling with nitrogen It heated up to. After the catalyst was sufficiently reduced with hydrogen, hydrogen and carbon tetrachloride were fed downflow at a molar ratio of 5: 1. As for the product, both gaseous and liquid components were analyzed using gas chromatography. After the start of the reaction, the reaction rate of carbon tetrachloride in 100 hours was 94%, and formation of chloroform (selectivity: 90%), perchloroethylene (selectivity: 5%) and the like were confirmed.

Next, the preparation example of the reduction catalyst which used the addition component element was shown, and the specific example of the liquid-phase reduction reaction using these reduction catalysts was shown.

Preparation Example 1

Coconut activated carbon powder as carrier (average particle size 10-20 100 g of ion-exchanged water 1 Was put in. Ruthenium chloride and gold acid were each dissolved in ion-exchanged water in an amount equivalent to 5% of the weight of the carrier at a weight ratio of 9: 1. Reduced with an aqueous solution of hydrazine, washed with ion-exchanged water and washed with 110 Dried over.

Preparation Example 2

Acetylene black powder as carrier (average particle size 1 100 g of ion-exchanged water 1 Was put in. Rhodium chloride and gold acid were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 95: 5 by weight of the metal component. Reduced with an aqueous solution of sodium borohydride, washed with ion-exchanged water and washed with 110 Dried over.

Preparation Example 3

Pitch-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Palladium chloride and gold acid were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a weight ratio of 8: 2. Reduced with an aqueous solution of hydrazine, washed with ion-exchanged water and washed with 110 Dried over.

Preparation Example 4

Pitch-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Nickel chloride, chloroplatinic acid and gold chloride were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 5: 4: 1 by weight of the metal component. Reduced with an aqueous solution of sodium borohydride, washed with ion-exchanged water and washed with 110 Dried over.

Preparation Example 5

Wood-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Platinum chloride and chlorochloric acid were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 9: 1 by weight of the metal component. Reduced with an aqueous solution of sodium borohydride, washed with ion-exchanged water and washed with 110 Dried over.

Preparation Example 6

Palm husk activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. The nitrates of ruthenium chloride and diamine were dissolved in ion-exchanged water in an amount equivalent to 5% of the weight of the carrier at a ratio of 85:15 by weight of the metal components, respectively. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of sodium borohydride. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 7

Palm husk activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Nitrate salts of rhodium chloride and diamine were dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier, respectively, at a weight ratio of 9: 1 of the metal component. After reducing to an aqueous solution of hydrazine, washing with ion-exchanged water and washing with 110 Dried over.

Preparation Example 8

Pitch-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Palladium chloride and diamine were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 95: 5 by weight of the metal component. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of hydrazine. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 9

Coconut activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Platinum chloride and diamine were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a weight ratio of 9: 1 of the metal component, respectively. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of hydrazine. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 10

Palm husk activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Ruthenium chloride and copper chloride were dissolved in ion-exchanged water in an amount equivalent to 5% of the weight of the carrier at a ratio of 95: 5 by weight of the metal component, respectively. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of sodium borohydride. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 11

Wood-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Rhodium chloride and copper chloride were dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 9: 1 by weight of the metal components, respectively. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of hydrazine. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 12

Pitch-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Palladium chloride and copper chloride were each dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 95: 5 by weight of the metal component. After adding ammonia water to make it alkaline, it was reduced by aqueous solution of hydrazine. Washed with ion-exchanged water and washed 110 Dried over.

Preparation Example 13

Palm-based activated carbon powder as carrier (average particle size 10 ~ 20 100 g of ion-exchanged water 1 Was put in. Platinum chloride and copper chloride were dissolved in ion-exchanged water in an amount equivalent to 2% of the weight of the carrier at a ratio of 9: 1 by weight of the metal components, respectively. After adding ammonia water to make it alkaline, it was reduced to an aqueous solution of hydrazine. Washed with ion-exchanged water and washed 110 Dried over.

Example 8

Inner capacity 2 1 liter of carbon tetrachloride was put into the autoclave, and 50 g of reduction catalysts prepared in Preparation Example 1 were added. Nitrogen sealed, 80 After the temperature was raised to, the hydrogen supply was started. Pressure is 5kg / cm ² G. As for the product, all of the gaseous components and liquid components were analyzed using gas chromatography. The reaction was continued by continuously supplying hydrogen at a rate of 3 mol to 1 mol of carbon tetrachloride. After the start of the reaction, the carbon tetrachloride reaction rate at 100 hours was 86%, and formation of chloroform (selectivity: 95%), hexachloroethane (selectivity: 5%) and the like were confirmed.

Example 9

The reaction temperature was 110 using the reduction catalyst according to Preparation Example 2. The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. The reaction rate of carbon tetrachloride in 100 hours after the start of the reaction was 78%, and formation of chloroform (selectivity: 85%), hexachloroethane (selectivity: 5%), methylene chloride (selectivity: 8%) and the like were confirmed.

Example 10

The reaction temperature was 100 by using the reduction catalyst according to Preparation Example 3. The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. The reaction rate of carbon tetrachloride at 100 hours after the start of the reaction was 85%, chloroform (selectivity: 90%), hexachloroethane (selectivity: 5%), pentachloroethane (selectivity: 2%), tetrachloroethylene (selectivity: 2%) was confirmed.

Example 11

The reaction was carried out in the same manner as in Example 8 except that the reduction catalyst according to Preparation Example 4 was used. After the start of the reaction, the reaction rate of carbon tetrachloride in 100 hours was 86%, and formation of chloroform (selectivity: 92%) and hexachloroethane (selectivity: 4%) was confirmed.

Example 12

The reaction temperature was 100 by using the reduction catalyst according to Preparation Example 5. The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. After the start of the reaction, the carbon tetrachloride reaction rate at 100 hours was 84%, and formation of chloroform (selectivity: 89%), hexachloroethane (selectivity: 6%) and the like were confirmed.

Example 13

The reaction was carried out in the same manner as in Example 8 except that the reduction catalyst according to Preparation Example 6 was used. After the start of the reaction, the reaction rate of carbon tetrachloride in 100 hours was 90%, and formation of chloroform (selectivity: 92%), hexachloroethane (selectivity: 3%) and the like were confirmed.

Example 14

Using a reduction catalyst according to Preparation Example 7, the reaction temperature was 110 The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. The reaction rate of carbon tetrachloride in 100 hours after the start of the reaction was 75%, and formation of chloroform (selectivity: 85%), hexachloroethane (selectivity: 6%), methylene chloride (selectivity: 7%) and the like were confirmed.

Example 15

Using a reduction catalyst according to Preparation Example 8, the reaction temperature was 100 The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. After the start of the reaction, the carbon tetrachloride reaction rate at 100 hours was 71%, chloroform (selectivity: 90%), hexachloroethane (selectivity: 4%), pentachloroethane (selectivity: 2%), tetrachloroethylene (selectivity: 2%) was confirmed.

Example 16

The reaction was carried out in the same manner as in Example 8 except that the reduction catalyst according to Preparation Example 9 was used. After the start of the reaction, the reaction rate of carbon tetrachloride in 100 hours was 84%, and formation of chloroform (selectivity: 97%), tetrachloroethylene (selectivity: 3%) and the like were confirmed.

Example 17

The reaction was carried out in the same manner as in Example 8 except that the reduction catalyst according to Preparation Example 10 was used. The reaction rate of carbon tetrachloride in 100 hours after the start of the reaction was 83%, chloroform (selectivity: 69%), hexachloroethane (selectivity: 28%), methylene chloride (selectivity: 1%), tetrachloroethylene (selectivity: 2 %) Was confirmed.

Example 18

The reaction temperature was 120 using the reduction catalyst according to Preparation Example 11. The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. The reaction rate of carbon tetrachloride in 100 hours after the start of the reaction was 84%, and formation of chloroform (selectivity: 87%), hexachloroethane (selectivity: 6%), methylene chloride (selectivity: 7%) and the like were confirmed.

Example 19

Using a reduction catalyst according to Preparation 12, the reaction temperature was 90 The reaction was carried out in the same manner as in Example 8 except that the reaction was carried out. After the start of the reaction, the carbon tetrachloride reaction rate at 100 hours was 74%, chloroform (selectivity: 89%), hexachloroethane (selectivity: 5%), pentachloroethane (selectivity: 2%), tetrachloroethylene (selectivity: 3%) was confirmed.

Example 20

The reaction was carried out in the same manner as in Example 8 except that the reduction catalyst according to Preparation Example 13 was used. After the start of the reaction, the reaction rate of carbon tetrachloride in 100 hours was 87%, and formation of chloroform (selectivity: 93%), hexachloroethane (selectivity: 5%) and the like were confirmed.

The present invention has the effect of producing a high yield of hydrous chloromethanes such as chloroform by reducing polychloromethanes, especially carbon tetrachloride, using hydrogen in the liquid phase as indicated in the Examples. Moreover, the method of this invention has the effect that even if it raises the reaction rate of raw material polychloromethane, water-containing chloromethanes, such as chloroform as a target object, can be obtained with a high selectivity. Moreover, in the method of this invention, since the side reaction which produces the impurity which impairs a catalyst activity can be suppressed effectively, it is extremely advantageous also from a catalyst life viewpoint.

Claims (6)

Preparation of water-containing chloromethanes, characterized in that polychloromethanes are reduced by hydrogen in a liquid stationary phase in the presence of a reducing catalyst containing at least one platinum group element selected from ruthenium, rhodium, palladium and platinum as a main component. Way. The preparation according to claim 1, wherein the reducing catalyst is a catalyst containing at least one platinum group element selected from ruthenium, rhodium, palladium and platinum as a main component and at least one element selected from group 11 elements added thereto. Way. The production method according to claim 2, wherein the additive component element in the reduction catalyst is at least one group 11 element selected from copper, silver, and gold. The production method according to claim 2, wherein the addition amount of the additive component element in the reduction catalyst is 0.01 to 50% by weight. The method of claim 1, wherein the reduction temperature is 0 To 200 Phosphorus manufacturing method. The method according to claim 1, wherein the polychloromethanes are carbon tetrachloride.